REU Faculty Mentors
Loren Buck, Ph.D.
Physiological Ecology, Endrocrinology
Research in my laboratory is focused on physiological ecology. I am interested in elucidating impacts of changing environmental conditions on the behavior and physiology (reproductive, metabolic, stress) of both marine and terrestrial organisms. The high latitude environment is dynamic. It is characterized by extreme intraanual, interannual, and interdecadal variation in temperature, currents, nutrients etc. which, in turn, profoundly affect species assemblages. Research projects in my laboratory address the mechanistic linkages whereby fluctuations in the environment impact the physiology and ultimate fitness of the individual. Although focused on the individual, these data allow for extrapolation to the population. This research not only serves a basic research function of describing and understanding the fundamental evolution of physiological adaptation, but also serves to define impacts of environmental change on growth and survival.
The science that I conduct incorporates a combination of field and laboratory approaches. Current funded projects are focused on organismal physiology (endocrinology, metabolism, circadian rhythms) of Arctic bird and mammal species. Data and samples are collected primarily from free-living animals or from captive, wild-caught animals. These studies typically involve personnel and students of various experience levels and involve a significant amount of teamwork in the field and laboratory.
Jennifer Burns, Ph.D.
Physiological ecology of diving vertebrates
Dr. Burns' research focuses on questions surrounding the physiological status of marine mammals and the behavioral strategies they use to find and exploit food resources. Particularly active areas of research in her laboratory focus on understanding how the age and physiological status of juvenile marine mammals influences their diving and foraging capacities, and on how differences in rates of physiological development impact life history traits. A variety of laboratory-based projects are available to REU students and students have the option of working in the areas of physiology or ecology. For example, students interested in physiological adaptations could address questions surrounding developmental changes in myoglobin levels or the binding affinities of the enzyme lactate dehydrogenase in walrus or seal pups. Alternatively, students interested in ecology might address questions surrounding the association of sea lions with particular water masses or the relationships between the duration of crabeater seal dives and prey density. A final project, unrelated to marine mammals, could examine growth and development of young arctic ground squirrels.
Khrystyne Duddleston, Ph.D.
Microbial ecology and host-microbe interactions
Research interests in Dr. Duddleston's lab focus on 1) microbial indicators of water quality and 2) host-microbe interactions. Microbial indicator research focuses on factors that affect the persistence and growth of fecal coliforms and fecal enterococci in Alaskan streams and lakes. Solving the problem of fecal contamination is always difficult, but is made more so in urbanized areas of Alaska by a) the contribution from wildlife to the bacterial load within streams and b) cool year round temperatures which may contribute to the persistence of fecal bacteria in sediments. Projects include studying factors that affect bacterial persistence and growth and using bacterial source tracking (Antibiotic Resistance Analysis) to determine the source of fecal pollution in the water bodies of urban areas and small village communities. Host-microbe interactions research focuses on the gut microflora of hibernating ground squirrels and marmots. While much light has been shed on the importance of the gut microbial community to overall health and development of animals in general, little is known about the gut microbiota of hibernating mammals, including ground squirrels and marmots. Current projects are geared toward examining a) how the gut microbial community in captive arctic ground squirrels changes over time, particularly at immergence, during hibernation, and at emergence, and b) how the gut flora of wild squirrels and marmots changes across the summer active season.
Fred A. Rainey, D.Phil.
Microbiology of Extreme Environments
Exploring, culturing, and describing microbial
diversity in extreme environments best describes current research interests of
Dr. Rainey's laboratory. The environments which we are currently studying
include arid and hyperarid lands, permafrost, glacial run off and surrounding
landscapes, as well as the volcanic island of Kasatochi in the Aleutian
Islands. Our aim is to determine how microorganisms survive in these extreme
environments, how they adapt to changes in these environments and their
persistence outside of their original microbial ecosystem. We use both
classical and molecular microbiological approaches in our research. Many of the
organisms that we isolate from these extreme environments represent novel taxa
that can be characterized and described as new species. In addition, RaineyLab
has a large collection of microorganisms from extreme environments
that students interested in bacterial taxonomy and systematics can work on as
part of their research experience. Projects carried out by undergraduate
researchers will provide both field and laboratory experiences and give
students a chance to be involved in interdisciplinary and collaborative
Dan Rinella, Ph.D.
Dr. Rinella's research focuses on the ecology of Alaska's fresh
waters, with an emphasis on juvenile salmonids, aquatic insects, and
their habitats. Several ongoing research projects have potential roles
for REU students. One study investigates the wintering ecology of
juvenile coho salmon on the Kenai Peninsula, where growth and survival
to smolting will be estimated for groups of tagged salmon that
overwintered in different types of habitats. Another study, also on the
Kenai Peninsula, investigates the interactive effects of contaminants
and invertebrate predators on rates of limb malformations in wood
frogs. A third study investigates the effect of climate change on the
availability of aquatic insect prey for shorebirds nesting in arctic
Alaska and Canada. These projects are collaborative and
multidisciplinary, and should give students experience into multiple
aspects of ecological investigation. Hands-on field data collection
will be central to any student research.
Jonathan Stecyk, Ph.D.
Cardiovascular physiology of anoxia-tolerant vertebrates
Most vertebrates die
within minutes of oxygen deprivation because the heart requires a continuous
supply of oxygen. For example, heart
attacks are one of the most common causes of death in the USA.However, in stark contrast to the majority of
vertebrates, some fish and turtle species can survive for weeks to months
without oxygen (termed anoxia), during which time their heart continues to beat.
Research in my
laboratory primarily focuses on
understanding how the heart of these champions of prolonged anoxia survival can
continue to function when deprived of oxygen, and how cardiac activity is
modulated.A number of research
techniques spanning multiple levels of biological organization are employed in
the laboratory, including measures of gene expression, patch-clamp experiments
on isolated cardiomyocytes, quantification of the contractile properties of
isolated heart tissue preparations and measurements of cardiovascular
parameters in live animals. Undergraduate researchers will have the opportunity
to learn and utilize one of these techniques while assessing a specific
research question.The data obtained will
contribute to the understanding of why some vertebrates can live for prolonged
time periods without oxygen, whereas other quickly perish.
Bjartmar Sveinbjornsson, Ph.D.
Treeline ecology and the physiological ecology of mosses and lichens
Dr. Sveinbjornsson's research focuses on the dynamics of the tundra-taiga boundary as well as the physiological ecology of mosses and lichens in arctic and subarctic ecosystems. His work addresses such questions as global change and arctic ecosystems, external forces and internal processes affecting treeline position, and physiological differences between alpine and subalpine lichen populations. REU student projects typically use a combination of laboratory and field-based approaches and utilize the forests and mountains surrounding Anchorage. For students interested in treeline ecology, projects could examine 1) how soil heterogeneity (nature of organic and nature mineral layers e.g. thickness, pH, organic matter, water relations, etc.) above and below the altitudinal treeline affects species density, or 2) how damage to trees at and below treeline affects growth. Potential projects in the area of moss and lichen ecology could address questions related to 1) correlations between species occurrence and overstory canopy conditions (vascular plant canopy closure) and substrate moisture holding capacity, or 2) moss and/or lichen drying rates in natural canopies as well as in modified canopies.
Frank von Hippel, Ph.D.
Ecotoxicology, Evolutionary Ecology & Conservation
The von Hippel lab studies problems in ecotoxicology,
evolutionary ecology and conservation biology using the stickleback as a model
system. REU students in von Hippel's lab
will be given the opportunity to analyze the morphology, behavior, physiology,
trophic ecology and/or genetics of sticklebacks or other freshwater fishes from
field sites in Alaska. On-going projects
include studies of mercury dynamics in aquatic food webs, trophic morphology,
speciation, and effects of contaminants on physiology and development.
Jeffrey Welker, Ph.D.
Physiological and ecosystem ecology of arctic tundra and boreal forests
Dr. Welker's research centers around four themes: a) Arctic tundra ecosystem responses to changes in climate in Alaska and Greenland, b) stable isotope geochemistry (δ18O & δD) of precipitation and the processes controlling the continental-scale spatial patterns and the decadal-scale oscillations in precipitation geochemistry, c) Boreal Forest carbon cycling and long-term changes in vegetation and atmospheric processes, d) marine-freshwater riparian ecosystem interactions and the role of salmon in controlling the nutrient cycles of terrestrial systems. These research activities provide several opportunities for REU projects. Student projects could easily link into on-going projects related to: a) carbon and nitrogen cycling responses of arctic tundra to long-term warming and deeper snow in winter, b) interannual variability in precipitation geochemistry in central Alaska, c) microclimate traits of urban boreal forests and the processes governing diurnal variance in soil respiration, d) soil N traits along a salmon density gradient in south-central Alaska. http://www.uaa.alaska.edu/enri/